Simplify packaging

[mkuratczyk]

Is your feature request related to a problem? Please describe.

1. The assets (filenames) contain the version which makes it hard to just download the latest
2. Assets are .tar.gz files that only contain 1 small file. Would be easier to just download the binary directly
3. The "unknown" in the Linux filename is confusing

Per discussion with @michaelklishin

Describe the solution you'd like

The goal is basically to be able to do something like this:

wget https://github.com/rabbitmq/rabbitmqadmin-ng/releases/latest/download/rabbitmqadmin-linux-x86_64 -O rabbitmqadmin
./rabbitmqadmin list queues

Describe alternatives you've considered

No response

Additional context

No response